xref: /btstack/src/classic/hsp_ag.c (revision 2d5e09d6d414e68e1ff909778712418ffa26b5d0)
1 /*
2  * Copyright (C) 2014 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 // *****************************************************************************
39 //
40 // Minimal setup for HSP Audio Gateway (!! UNDER DEVELOPMENT !!)
41 //
42 // *****************************************************************************
43 
44 #include "btstack_config.h"
45 
46 #include <stdint.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <string.h>
50 
51 #include "btstack_debug.h"
52 #include "btstack_event.h"
53 #include "btstack_memory.h"
54 #include "btstack_run_loop.h"
55 #include "classic/sdp_server.h"
56 #include "classic/sdp_query_rfcomm.h"
57 #include "hci.h"
58 #include "hci_cmd.h"
59 #include "hci_dump.h"
60 #include "hsp_ag.h"
61 #include "l2cap.h"
62 
63 #define RFCOMM_SERVER_CHANNEL 1
64 
65 #define HSP_HS_BUTTON_PRESS "AT+CKPD=200"
66 #define HSP_HS_AT_CKPD "AT+CKPD\r\n"
67 #define HSP_AG_OK "\r\nOK\r\n"
68 #define HSP_AG_ERROR "\r\nERROR\r\n"
69 #define HSP_AG_RING "\r\nRING\r\n"
70 #define HSP_MICROPHONE_GAIN "+VGM"
71 #define HSP_SPEAKER_GAIN "+VGS"
72 
73 #define HSP_HS_MICROPHONE_GAIN "AT+VGM="
74 #define HSP_HS_SPEAKER_GAIN "AT+VGS="
75 
76 static const char default_hsp_ag_service_name[] = "Audio Gateway";
77 
78 static bd_addr_t remote;
79 static uint8_t channel_nr = 0;
80 
81 static uint16_t mtu;
82 static uint16_t rfcomm_cid = 0;
83 static uint16_t sco_handle = 0;
84 static uint16_t rfcomm_handle = 0;
85 static btstack_timer_source_t hs_timeout;
86 
87 // static uint8_t connection_state = 0;
88 
89 static int ag_microphone_gain = -1;
90 static int ag_speaker_gain = -1;
91 static uint8_t ag_ring = 0;
92 static uint8_t ag_send_ok = 0;
93 static uint8_t ag_send_error = 0;
94 static uint8_t ag_num_button_press_received = 0;
95 static uint8_t ag_support_custom_commands = 0;
96 
97 static btstack_packet_callback_registration_t hci_event_callback_registration;
98 
99 typedef enum {
100     HSP_IDLE,
101     HSP_SDP_QUERY_RFCOMM_CHANNEL,
102     HSP_W4_SDP_EVENT_QUERY_COMPLETE,
103     HSP_W4_RFCOMM_CONNECTED,
104     HSP_W4_RING_ANSWER,
105     HSP_W4_USER_ACTION,
106     HSP_W2_CONNECT_SCO,
107     HSP_W4_SCO_CONNECTED,
108     HSP_ACTIVE,
109     HSP_W2_DISCONNECT_SCO,
110     HSP_W4_SCO_DISCONNECTED,
111     HSP_W2_DISCONNECT_RFCOMM,
112     HSP_W4_RFCOMM_DISCONNECTED,
113     HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN
114 } hsp_state_t;
115 
116 static hsp_state_t hsp_state = HSP_IDLE;
117 
118 
119 static hsp_ag_callback_t hsp_ag_callback;
120 
121 static void hsp_run();
122 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
123 static void handle_query_rfcomm_event(uint8_t packet_type, uint8_t *packet, uint16_t size);
124 
125 static void dummy_notify(uint8_t * event, uint16_t size){}
126 
127 void hsp_ag_register_packet_handler(hsp_ag_callback_t callback){
128     if (callback == NULL){
129         callback = &dummy_notify;
130     }
131     hsp_ag_callback = callback;
132 }
133 
134 static void emit_event(uint8_t event_subtype, uint8_t value){
135     if (!hsp_ag_callback) return;
136     uint8_t event[4];
137     event[0] = HCI_EVENT_HSP_META;
138     event[1] = sizeof(event) - 2;
139     event[2] = event_subtype;
140     event[3] = value; // status 0 == OK
141     (*hsp_ag_callback)(event, sizeof(event));
142 }
143 
144 static void emit_event_audio_connected(uint8_t status, uint16_t handle){
145     if (!hsp_ag_callback) return;
146     uint8_t event[6];
147     event[0] = HCI_EVENT_HSP_META;
148     event[1] = sizeof(event) - 2;
149     event[2] = HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE;
150     event[3] = status;
151     little_endian_store_16(event, 4, handle);
152     (*hsp_ag_callback)(event, sizeof(event));
153 }
154 
155 void hsp_ag_create_service(uint8_t * service, uint32_t service_record_handle, int rfcomm_channel_nr, const char * name){
156     uint8_t* attribute;
157     de_create_sequence(service);
158 
159     // 0x0000 "Service Record Handle"
160     de_add_number(service, DE_UINT, DE_SIZE_16, SDP_ServiceRecordHandle);
161     de_add_number(service, DE_UINT, DE_SIZE_32, service_record_handle);
162 
163     // 0x0001 "Service Class ID List"
164     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ServiceClassIDList);
165     attribute = de_push_sequence(service);
166     {
167         //  "UUID for PAN Service"
168         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_Headset_AG);
169         de_add_number(attribute, DE_UUID, DE_SIZE_16, SDP_GenericAudio);
170     }
171     de_pop_sequence(service, attribute);
172 
173     // 0x0004 "Protocol Descriptor List"
174     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_ProtocolDescriptorList);
175     attribute = de_push_sequence(service);
176     {
177         uint8_t* l2cpProtocol = de_push_sequence(attribute);
178         {
179             de_add_number(l2cpProtocol,  DE_UUID, DE_SIZE_16, SDP_L2CAPProtocol);
180         }
181         de_pop_sequence(attribute, l2cpProtocol);
182 
183         uint8_t* rfcomm = de_push_sequence(attribute);
184         {
185             de_add_number(rfcomm,  DE_UUID, DE_SIZE_16, SDP_RFCOMMProtocol);  // rfcomm_service
186             de_add_number(rfcomm,  DE_UINT, DE_SIZE_8,  rfcomm_channel_nr);  // rfcomm channel
187         }
188         de_pop_sequence(attribute, rfcomm);
189     }
190     de_pop_sequence(service, attribute);
191 
192     // 0x0005 "Public Browse Group"
193     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BrowseGroupList); // public browse group
194     attribute = de_push_sequence(service);
195     {
196         de_add_number(attribute,  DE_UUID, DE_SIZE_16, SDP_PublicBrowseGroup);
197     }
198     de_pop_sequence(service, attribute);
199 
200     // 0x0009 "Bluetooth Profile Descriptor List"
201     de_add_number(service,  DE_UINT, DE_SIZE_16, SDP_BluetoothProfileDescriptorList);
202     attribute = de_push_sequence(service);
203     {
204         uint8_t *sppProfile = de_push_sequence(attribute);
205         {
206             de_add_number(sppProfile,  DE_UUID, DE_SIZE_16, SDP_HSP);
207             de_add_number(sppProfile,  DE_UINT, DE_SIZE_16, 0x0102); // Verision 1.2
208         }
209         de_pop_sequence(attribute, sppProfile);
210     }
211     de_pop_sequence(service, attribute);
212 
213     // 0x0100 "Service Name"
214     de_add_number(service,  DE_UINT, DE_SIZE_16, 0x0100);
215     if (name){
216         de_add_data(service,  DE_STRING, strlen(name), (uint8_t *) name);
217     } else {
218         de_add_data(service,  DE_STRING, strlen(default_hsp_ag_service_name), (uint8_t *) default_hsp_ag_service_name);
219     }
220 }
221 
222 static int hsp_ag_send_str_over_rfcomm(uint16_t cid, char * command){
223     if (!rfcomm_can_send_packet_now(cid)) return 1;
224     int err = rfcomm_send(cid, (uint8_t*) command, strlen(command));
225     if (err){
226         printf("rfcomm_send -> error 0X%02x", err);
227         return err;
228     }
229     printf("Send string: \"%s\"\n", command);
230     return err;
231 }
232 
233 void hsp_ag_support_custom_commands(int enable){
234     ag_support_custom_commands = enable;
235 }
236 
237 int hsp_ag_send_result(char * result){
238     if (!ag_support_custom_commands) return 1;
239     return hsp_ag_send_str_over_rfcomm(rfcomm_cid, result);
240 }
241 
242 static void hsp_ag_reset_state(void){
243     hsp_state = HSP_IDLE;
244 
245     rfcomm_cid = 0;
246     rfcomm_handle = 0;
247     sco_handle = 0;
248 
249     ag_send_ok = 0;
250     ag_send_error = 0;
251     ag_ring = 0;
252 
253     ag_num_button_press_received = 0;
254     ag_support_custom_commands = 0;
255 
256     ag_microphone_gain = -1;
257     ag_speaker_gain = -1;
258 }
259 
260 void hsp_ag_init(uint8_t rfcomm_channel_nr){
261     // register for HCI events
262     hci_event_callback_registration.callback = &packet_handler;
263     hci_add_event_handler(&hci_event_callback_registration);
264 
265     // init L2CAP
266     l2cap_init();
267 
268     rfcomm_init();
269     rfcomm_register_service(packet_handler, rfcomm_channel_nr, 0xffff);  // reserved channel, mtu limited by l2cap
270 
271     sdp_query_rfcomm_register_callback(handle_query_rfcomm_event);
272 
273     hsp_ag_reset_state();
274 }
275 
276 void hsp_ag_connect(bd_addr_t bd_addr){
277     if (hsp_state != HSP_IDLE) return;
278     hsp_state = HSP_SDP_QUERY_RFCOMM_CHANNEL;
279     memcpy(remote, bd_addr, 6);
280     hsp_run();
281 }
282 
283 void hsp_ag_disconnect(void){
284     switch (hsp_state){
285         case HSP_ACTIVE:
286             hsp_state = HSP_W2_DISCONNECT_SCO;
287             break;
288         case HSP_W2_CONNECT_SCO:
289             hsp_state = HSP_W2_DISCONNECT_RFCOMM;
290             break;
291 
292         case HSP_W4_RFCOMM_CONNECTED:
293         case HSP_W4_SCO_CONNECTED:
294             hsp_state = HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN;
295             break;
296         default:
297             return;
298     }
299     hsp_run();
300 }
301 
302 void hsp_ag_set_microphone_gain(uint8_t gain){
303     if (gain < 0 || gain >15) {
304         printf("Gain must be in interval [0..15], it is given %d\n", gain);
305         return;
306     }
307     ag_microphone_gain = gain;
308     hsp_run();
309 }
310 
311 // AG +VGS=5  [0..15] ; HS AT+VGM=6 | AG OK
312 void hsp_ag_set_speaker_gain(uint8_t gain){
313     if (gain < 0 || gain >15) {
314         printf("Gain must be in interval [0..15], it is given %d\n", gain);
315         return;
316     }
317     ag_speaker_gain = gain;
318     hsp_run();
319 }
320 
321 static void hsp_timeout_handler(btstack_timer_source_t * timer){
322     ag_ring = 1;
323 }
324 
325 static void hsp_timeout_start(void){
326     btstack_run_loop_remove_timer(&hs_timeout);
327     btstack_run_loop_set_timer_handler(&hs_timeout, hsp_timeout_handler);
328     btstack_run_loop_set_timer(&hs_timeout, 2000); // 2 seconds timeout
329     btstack_run_loop_add_timer(&hs_timeout);
330 }
331 
332 static void hsp_timeout_stop(void){
333     btstack_run_loop_remove_timer(&hs_timeout);
334 }
335 
336 void hsp_ag_start_ringing(void){
337     if (hsp_state != HSP_W2_CONNECT_SCO) return;
338     ag_ring = 1;
339     hsp_state = HSP_W4_RING_ANSWER;
340     hsp_timeout_start();
341 }
342 
343 void hsp_ag_stop_ringing(void){
344     ag_ring = 0;
345     ag_num_button_press_received = 0;
346     hsp_state = HSP_W2_CONNECT_SCO;
347     hsp_timeout_stop();
348 }
349 
350 static void hsp_run(void){
351     int err;
352 
353     if (ag_send_ok){
354         ag_send_ok = 0;
355         err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
356         if (err){
357             ag_send_ok = 1;
358         }
359         return;
360     }
361 
362     if (ag_send_error){
363         ag_send_error = 0;
364         err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
365         if (err) {
366             ag_send_error = 1;
367         }
368         return;
369     }
370 
371     switch (hsp_state){
372         case HSP_SDP_QUERY_RFCOMM_CHANNEL:
373             hsp_state = HSP_W4_SDP_EVENT_QUERY_COMPLETE;
374             printf("Start SDP query %s, 0x%02x\n", bd_addr_to_str(remote), SDP_HSP);
375             sdp_query_rfcomm_channel_and_name_for_uuid(remote, SDP_HSP);
376             break;
377 
378         case HSP_W4_RING_ANSWER:
379             if (ag_ring){
380                 ag_ring = 0;
381                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
382                 if (err) {
383                     ag_ring = 1;
384                 }
385                 break;
386             }
387 
388             if (!ag_num_button_press_received) break;
389             ag_send_ok = 0;
390 
391             ag_num_button_press_received = 0;
392             hsp_state = HSP_W2_CONNECT_SCO;
393 
394             err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
395             if (err) {
396                 hsp_state = HSP_W4_RING_ANSWER;
397                 ag_num_button_press_received = 1;
398             }
399             break;
400         case HSP_W2_CONNECT_SCO:
401             if (!hci_can_send_command_packet_now()) break;
402             hsp_state = HSP_W4_SCO_CONNECTED;
403             hci_send_cmd(&hci_setup_synchronous_connection, rfcomm_handle, 8000, 8000, 0xFFFF, hci_get_sco_voice_setting(), 0xFF, 0x003F);
404             break;
405 
406         case HSP_W2_DISCONNECT_SCO:
407             ag_num_button_press_received = 0;
408 
409             hsp_state = HSP_W4_SCO_DISCONNECTED;
410             gap_disconnect(sco_handle);
411             break;
412 
413         case HSP_W2_DISCONNECT_RFCOMM:
414             hsp_state = HSP_W4_RFCOMM_DISCONNECTED;
415             rfcomm_disconnect(rfcomm_cid);
416             break;
417         case HSP_ACTIVE:
418 
419             if (ag_microphone_gain >= 0){
420                 int gain = ag_microphone_gain;
421                 ag_microphone_gain = -1;
422                 char buffer[10];
423                 sprintf(buffer, "%s=%d\r\n", HSP_MICROPHONE_GAIN, gain);
424                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
425                 if (err) {
426                     ag_microphone_gain = gain;
427                 }
428                 break;
429             }
430 
431             if (ag_speaker_gain >= 0){
432                 int gain = ag_speaker_gain;
433                 ag_speaker_gain = -1;
434                 char buffer[10];
435                 sprintf(buffer, "%s=%d\r\n", HSP_SPEAKER_GAIN, gain);
436                 err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
437                 if (err) {
438                     ag_speaker_gain = gain;
439                 }
440                 break;
441             }
442             break;
443         default:
444             break;
445     }
446 }
447 
448 
449 static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
450     // printf("packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
451     if (packet_type == RFCOMM_DATA_PACKET){
452         while (size > 0 && (packet[0] == '\n' || packet[0] == '\r')){
453             size--;
454             packet++;
455         }
456 
457         if (strncmp((char *)packet, HSP_HS_BUTTON_PRESS, strlen(HSP_HS_BUTTON_PRESS)) == 0){
458             printf("Received button press %s\n", HSP_HS_BUTTON_PRESS);
459             ag_num_button_press_received++;
460             ag_send_ok = 1;
461             if (hsp_state == HSP_ACTIVE && ag_num_button_press_received >=2){
462                 ag_num_button_press_received = 0;
463                 hsp_state = HSP_W2_DISCONNECT_SCO;
464             }
465         } else if (strncmp((char *)packet, HSP_HS_MICROPHONE_GAIN, strlen(HSP_HS_MICROPHONE_GAIN)) == 0){
466             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_MICROPHONE_GAIN)]);
467             ag_send_ok = 1;
468             emit_event(HSP_SUBEVENT_MICROPHONE_GAIN_CHANGED, gain);
469 
470         } else if (strncmp((char *)packet, HSP_HS_SPEAKER_GAIN, strlen(HSP_HS_SPEAKER_GAIN)) == 0){
471             uint8_t gain = (uint8_t)atoi((char*)&packet[strlen(HSP_HS_SPEAKER_GAIN)]);
472             ag_send_ok = 1;
473             emit_event(HSP_SUBEVENT_SPEAKER_GAIN_CHANGED, gain);
474 
475         } else if (strncmp((char *)packet, "AT+", 3) == 0){
476             ag_send_error = 1;
477             if (!hsp_ag_callback) return;
478             // re-use incoming buffer to avoid reserving large buffers - ugly but efficient
479             uint8_t * event = packet - 3;
480             event[0] = HCI_EVENT_HSP_META;
481             event[1] = size + 1;
482             event[2] = HSP_SUBEVENT_HS_COMMAND;
483             (*hsp_ag_callback)(event, size+3);
484         }
485 
486         hsp_run();
487         return;
488     }
489 
490     if (packet_type != HCI_EVENT_PACKET) return;
491     uint8_t event = packet[0];
492     bd_addr_t event_addr;
493     uint16_t handle;
494 
495     switch (event) {
496         case BTSTACK_EVENT_STATE:
497             // BTstack activated, get started
498             if (packet[2] == HCI_STATE_WORKING){
499                 printf("BTstack activated, get started .\n");
500             }
501             break;
502 
503         case HCI_EVENT_PIN_CODE_REQUEST:
504             // inform about pin code request
505             printf("Pin code request - using '0000'\n\r");
506             reverse_bd_addr(&packet[2], event_addr);
507             hci_send_cmd(&hci_pin_code_request_reply, &event_addr, 4, "0000");
508             break;
509         case HCI_EVENT_SYNCHRONOUS_CONNECTION_COMPLETE:{
510             int index = 2;
511             uint8_t status = packet[index++];
512             sco_handle = little_endian_read_16(packet, index);
513             index+=2;
514             bd_addr_t address;
515             memcpy(address, &packet[index], 6);
516             index+=6;
517             uint8_t link_type = packet[index++];
518             uint8_t transmission_interval = packet[index++];  // measured in slots
519             uint8_t retransmission_interval = packet[index++];// measured in slots
520             uint16_t rx_packet_length = little_endian_read_16(packet, index); // measured in bytes
521             index+=2;
522             uint16_t tx_packet_length = little_endian_read_16(packet, index); // measured in bytes
523             index+=2;
524             uint8_t air_mode = packet[index];
525 
526             if (status != 0){
527                 log_error("(e)SCO Connection failed, status %u", status);
528                 emit_event_audio_connected(status, sco_handle);
529                 break;
530             }
531             switch (link_type){
532                 case 0x00:
533                     printf("SCO Connection established. \n");
534                     if (transmission_interval != 0) log_error("SCO Connection: transmission_interval not zero: %d.", transmission_interval);
535                     if (retransmission_interval != 0) log_error("SCO Connection: retransmission_interval not zero: %d.", retransmission_interval);
536                     if (rx_packet_length != 0) log_error("SCO Connection: rx_packet_length not zero: %d.", rx_packet_length);
537                     if (tx_packet_length != 0) log_error("SCO Connection: tx_packet_length not zero: %d.", tx_packet_length);
538                     break;
539                 case 0x02:
540                     printf("eSCO Connection established. \n");
541                     break;
542                 default:
543                     log_error("(e)SCO reserved link_type 0x%2x", link_type);
544                     break;
545             }
546             log_info("sco_handle 0x%2x, address %s, transmission_interval %u slots, retransmission_interval %u slots, "
547                  " rx_packet_length %u bytes, tx_packet_length %u bytes, air_mode 0x%2x (0x02 == CVSD)", sco_handle,
548                  bd_addr_to_str(address), transmission_interval, retransmission_interval, rx_packet_length, tx_packet_length, air_mode);
549 
550             if (hsp_state == HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN){
551                 hsp_state = HSP_W2_DISCONNECT_SCO;
552                 break;
553             }
554 
555             hsp_state = HSP_ACTIVE;
556             emit_event_audio_connected(status, sco_handle);
557             break;
558         }
559 
560         case RFCOMM_EVENT_INCOMING_CONNECTION:
561             // data: event (8), len(8), address(48), channel (8), rfcomm_cid (16)
562             if (hsp_state != HSP_IDLE) return;
563 
564             reverse_bd_addr(&packet[2], event_addr);
565             rfcomm_cid = little_endian_read_16(packet, 9);
566             printf("RFCOMM channel %u requested for %s\n", packet[8], bd_addr_to_str(event_addr));
567             rfcomm_accept_connection(rfcomm_cid);
568 
569             hsp_state = HSP_W4_RFCOMM_CONNECTED;
570 
571             break;
572 
573         case RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE:
574             printf("RFCOMM_EVENT_OPEN_CHANNEL_COMPLETE packet_handler type %u, packet[0] %x\n", packet_type, packet[0]);
575             // data: event(8), len(8), status (8), address (48), handle(16), server channel(8), rfcomm_cid(16), max frame size(16)
576             if (packet[2]) {
577                 printf("RFCOMM channel open failed, status %u\n", packet[2]);
578                 hsp_ag_reset_state();
579                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, packet[2]);
580             } else {
581                 // data: event(8) , len(8), status (8), address (48), handle (16), server channel(8), rfcomm_cid(16), max frame size(16)
582                 rfcomm_handle = little_endian_read_16(packet, 9);
583                 rfcomm_cid = little_endian_read_16(packet, 12);
584                 mtu = little_endian_read_16(packet, 14);
585                 printf("RFCOMM channel open succeeded. New RFCOMM Channel ID %u, max frame size %u, state %d\n", rfcomm_cid, mtu, hsp_state);
586 
587                 switch (hsp_state){
588                     case HSP_W4_RFCOMM_CONNECTED:
589                         ag_num_button_press_received = 0;
590                         hsp_state = HSP_W2_CONNECT_SCO;
591                         break;
592                     case HSP_W4_CONNECTION_ESTABLISHED_TO_SHUTDOWN:
593                         hsp_state = HSP_W2_DISCONNECT_RFCOMM;
594                         break;
595                     default:
596                         printf("no valid state\n");
597                         break;
598                 }
599             }
600             break;
601 
602         case HCI_EVENT_DISCONNECTION_COMPLETE:
603             if (hsp_state != HSP_W4_SCO_DISCONNECTED){
604                 log_info("received gap disconnect in wrong hsp state");
605             }
606             handle = little_endian_read_16(packet,3);
607             if (handle == sco_handle){
608                 printf("SCO disconnected, w2 disconnect RFCOMM\n");
609                 sco_handle = 0;
610                 hsp_state = HSP_W2_DISCONNECT_RFCOMM;
611                 break;
612             }
613             break;
614 
615         case RFCOMM_EVENT_CHANNEL_CLOSED:
616             if (hsp_state != HSP_W4_RFCOMM_DISCONNECTED){
617                 log_info("received RFCOMM disconnect in wrong hsp state");
618             }
619             printf("RFCOMM channel closed\n");
620             hsp_ag_reset_state();
621             emit_event(HSP_SUBEVENT_AUDIO_DISCONNECTION_COMPLETE,0);
622             break;
623         default:
624             break;
625     }
626     hsp_run();
627 }
628 
629 static void handle_query_rfcomm_event(uint8_t packet_type, uint8_t *packet, uint16_t size){
630     switch (packet[0]){
631         case SDP_EVENT_QUERY_RFCOMM_SERVICE:
632             channel_nr = sdp_event_query_rfcomm_service_get_rfcomm_channel(packet);
633             printf("** Service name: '%s', RFCOMM port %u\n", sdp_event_query_rfcomm_service_get_name(packet), channel_nr);
634             break;
635         case SDP_EVENT_QUERY_COMPLETE:
636             if (channel_nr > 0){
637                 hsp_state = HSP_W4_RFCOMM_CONNECTED;
638                 printf("RFCOMM create channel. state %d\n", HSP_W4_RFCOMM_CONNECTED);
639                 rfcomm_create_channel(remote, channel_nr, NULL);
640                 break;
641             }
642             hsp_ag_reset_state();
643             printf("Service not found, status %u.\n", sdp_event_query_complete_get_status(packet));
644             if (sdp_event_query_complete_get_status(packet)){
645                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, sdp_event_query_complete_get_status(packet));
646             } else {
647                 emit_event(HSP_SUBEVENT_AUDIO_CONNECTION_COMPLETE, SDP_SERVICE_NOT_FOUND);
648             }
649             break;
650         default:
651             break;
652     }
653 }
654 
655 
656